Hove, Sibylle Van

INTRODUCTION: Chronic gastroduodenal disorders are highly prevalent and encompass heterogeneous pathophysiology. Autonomic dysfunction may contribute, but its relative contribution to disease pathophysiology and symptoms is unclear. This study aimed to clarify the contributions of autonomic dysfunction in gastroduodenal disorders and symptom associations using multimodal testing, hypothesizing that distinct disorder subgroups would be revealed. METHODS: This prospective observational cohort study included 80 patients with chronic gastroduodenal symptoms. Participants underwent expert clinician-led autonomic evaluation, body surface gastric mapping (BSGM; Gastric Alimetry, New Zealand), and gastric emptying scintigraphy testing. BSGM phenotyping, gastric emptying cutoffs, and autonomic criteria followed standard criteria. RESULTS: Gastroparesis was diagnosed in 27 (33.8%) patients. Autonomic dysfunction was present in 21 (26.3%) patients, and abnormal BSGM in 20 (25%). Autonomic dysfunction and abnormal BSGM were both more prevalent in gastroparesis (51.9% vs 13.2%, P = 0.001; and 44.4% vs 15.1%, P = 0.005, respectively). However, these diagnoses tended not to overlap, with patients having autonomic dysfunction generally exhibiting normal BSGM tests. Autonomic dysfunction independently predicted delayed gastric emptying (OR 13.8, P < 0.001) and was associated with earlier meal responses (higher meal response ratio, P = 0.04) and worse postprandial distress symptoms ( P < 0.05). DISCUSSION: Autonomic dysfunction independently predicted delayed gastric emptying and revealed a gastroparesis mechanism distinct from gastric myoelectrical impairment. Autonomic dysfunction altered the postprandial gastric motor response and was associated with a greater symptom burden. Multimodal physiological testing including autonomic profiling reveals distinct mechanistic subgroups in patients with chronic gastroduodenal symptoms.

ABSTRACT Background Chronic neurogastroduodenal disorders are challenging to manage, with therapy often initiated on a trial and error basis. Prokinetics play a significant role in management, but responses are variable and have been associated with adverse events, impacting widespread use. We investigated whether body surface gastric mapping (BSGM) biomarkers (using Gastric Alimetry) could inform patient selection for prokinetic therapy. Methods Patients with chronic gastroduodenal symptoms taking oral prokinetic agents, regardless of gastric emptying status, were prospectively recruited and underwent BSGM (30 m baseline, 482 kcal standardized meal, 4 h postprandial recording) while off‐prokinetic agents. Patients were followed up with daily symptom diaries. A subset was compared to matched patients not taking prokinetic agents. Prokinetic responders were defined based on symptom improvement greater than a minimum clinically important difference methodology. Key Results Forty‐two patients (88% female; median age 36; median BMI 26) taking prokinetics were analyzed. Prokinetic prescribing, compared to matched patients, was independent of BSGM metrics ( p > 0.15). In patients on existing prokinetics (withheld for BSGM), lower amplitudes predicted reduced symptom burden, whereas low rhythm stability predicted a worse symptom burden ( p < 0.05). In prokinetic‐naive patients (i.e., started on a prokinetic during the study), a lower postprandial amplitude predicted responders (mean 37.5 ± 10.6 uV in responders [ n = 5] vs. mean 54.8 ± 6.6 uV among nonresponders [ n = 3], p = 0.047). Conclusions Gastric Alimetry biomarkers may help in the prediction of prokinetic response in patients with chronic gastroduodenal symptoms. Lower postprandial amplitudes, indicating a reduced meal response, appear to predict benefit, while impaired rhythm stability predicted poorer therapeutic response.